Process and apparatus for the conveyance of an explosive oil



0 United States Patent [111 3,523,543

[72] Inventors Gerhard Martin 2,383,707 8/1945 Carl 23/266XR Troisdorl,Germany; 2,694,404 1 l/ l 954 Luft et al. 137/ I Werner Sassmannshausen,Bergisch- Gladbach, Germany; Jakob Franz Roth, FOREIGN PATENTS p m yl,003,856 9/1965 ,Great Britain l37/l [21] Appl. No. 668,016

:gfs Primary Examiner- Robert G. Nilson [73] Assignee Dynamit NobelAktiengesellschaft, mmmey' cralg Antonen" Stewart &

Troisdorl, Germany [32] Priority Sept. 14, 1966 [33] Germany [31]ABSTRACT: The present disclosure relates to a process and ap aratus forthe conve ance of an ex losive oil usin an F I 1 y I p g a I 54] PROCESSAND APPARATUS FOR THE emulsifying means, More particularly, the presentdisclosure IS CONVEYANCE OF AN EXPLOSIVE OIL directed to a process andapparatus for the conveyance of an 27 Claims3Drawing Figs explos ve Ollfrom a container to a point of consumption wherein water IS drawn intothe conveying system during the [52] LS-Cl 137/1, i itiation of theprocess as well as before shutting off the 2 3 /5 system, that is,during the critical hases of the o eration of P P [51] lltLCl ..C06b21/02 th y te a d a ordingly the entire conveying system is Fieldcompletely filled with water during these operational phases [3, 154,I72, 233, 590'; 22/64, 23/266 and explosive oil is introduced into thesystem only when the 56 R r d emulsifying means has substantiallyreached its full suction 1 e erences power. As a result of thisoperation there is no air present or UNITED STATES PATENTS introducedinto the conduit conveyin system and thus, ex lo- 8 P 321,744 7/1 885Millner 137/577 sive oil can be conveyed with little or no danger.

Patentd Aug. 11, 1970 Sheet PERCUSSION SENSITIVITY -MAx O I 2 3 4 5 6 78 9 IO AIR BUBBLES mm FIG. 'I

INVENTORS GERHARD MARTIN WERNER SASSMANNSHAUSEN JAKOB FRANZ ROTHPatented Aug. 11, 1970 3,523,543

Sheet 2 012 INVENTORS GERHARD MARTIN WERNER SASSMANNSHAUSEN JAKOB FRANZROTH BY r ATTORNEYS PROCESS AND APPARATUS FOR THE CONVEYANCE OF ANEXPLOSIVE OIL BACKGROUND OF THE INVENTION The present invention relatesto a process and apparatus for the conveyance of an explosive oil suchas nitroglycerin from one location to another. More particularly, thepresent invention is concerned with a process and apparatus whichprevents air from being introduced into the conduit conveying system andthus substantially eliminates the dangers normally associated with theconveyance of explosive oils.

It is known to transport liquid nitric acid esters, for example anexplosive oil such as nitroglycerin in transport lines by means of aninjector. In such a process the explosive oil is drawn into the systemfrom a storage tank by a hydraulically operated injector using a suctionnipple or a suction pipe, is emulsified with the propellant waterdownstream of the propellant nozzle of the injector and is then furtherconducted in the form of an emulsion through the pipeline to theconsumption site or the like where the emulsion is then again separatedin a separator into explosive oil and water.

As is well known, emulsified explosive oil can be transported throughconduits with relatively little danger. However, since the injector mustinitially withdraw pure explosive oil from the storage tank or the like,there are still considerable risks associated with the use of thepreviously known methods for conducting explosive oil by means of aninjector. For example, one of these risks is the danger that during thetransportation of the explosive oil air enters or is drawn into the oil.As can be readily seen from the diagram of FIGURE 1 which represents therelationship between the shock sensitivity of explosive oil and the sizeof air bubbles present therein, the shock sensitivity of the explosiveoil increases from 26.5 kpm/cm in the absence of air to about 1.86kpm/cm in the presence of small air bubbles having a diameter of aboutlmm, to about 0.8 kpm/cm in the presence of air bubbles having adiameter of about 2mm, and finally to almost kpm/cm in the presence ofair bubbles having a diameter of about 8mm.

The cause for such a strong increase in the shock sensitivity of theexplosive oil is to be seen in the fact that the impedance or the shockresistance coefficient of air amounts to only l/5,000 of the impedanceof liquids, that is, of explosive oil as well as water. Accordingly,shocks are drawn into the readily compressible air with an asymmetricalimplosion of the air bubbles and the production of so called hot spots.The same phenomena also occurs when gas or steam bubbles are produced bycavitation and collapse.

A further dangerous factor is also represented by the presence of valvesor control elements provided in or at conduits for the conveyance ofpure and/or emulsified explosive oil, as required, for example, inGerman Auslegeschrift (published application) 1,085,448, British Patent320,778 and Belgian Patent 529,430 in the previously known systems. Evenif the dangers which arise from the use of metallic contact or sealingsurfaces are avoided by the utilization of squeegee valves, diaphragmmultiway valves, membrane valves, or the like, there still remains thedanger of cavitation due to sudden change in cross section or theformation of a vacuum by the injector.

An examination of the conventional injector conveying systems presentlyknown with respect to the above-mentioned disadvantages results in thefollowing observations:

a) With respect to the arrangement of the injector above the explosiveoil.

Due to the stream of propellant water in the injector, a vacuum isproduced in the suction pipe effecting the intake of the explosive oil.For control purposes, a valve is necessary in the suction pipe. Uponopening of the valve, a shock is exerted upon the explosive oil which,in conjunction with any air bubbles present and/or in conjunction withcavitation, can become an acute danger. Although a considerableweakening of the explosive oil impact can be achieved by theincorporation of a bypass line, the dangers associated with valves andcontrol elements are not at all eliminated thereby, not considering thefact that the bypass line in certain cases generally requires anadditional valve to be added. Furthermore, in this arrangement there isalso the danger that the explosive oil tank may become emptied andconsequently, as mentioned above, air may be deleteriously drawn intothe system. Finally, any leak in the injector creates the danger of theintroduction of air into the system.

b) Arrangement of the injector at the level of the explosive oil orbelow said level.

In this arrangement, when the device is inoperative the injector as wellas the connecting conduits are filled with explosive oil. Consequently,when the device starts operating, at

least the explosive oil present downstream of the injector in theconduit will be conveyed in the form of a plug of pure explosive oil infront of the emulsion following thereafter, which represents a dangeroussituation. Another dangerous factor is also represented by explosive oilwhich has penetrated into the propellant water conduit, since this oilis pressed through the injector nozzle at a high speed when theoperation of the system is initiated.

With respect to the aforementioned type of injector arrangements, itshould be noted that without the use of valves, be it in the suctionline leading from the explosive oil tank to the injector or in theemulsion line leading from the injector to the consumer site, it hasbeen heretofore impossible to conduct a preliminary rinsing or apost-rinsing step or an operation in accordance with the so-callcdinoculation method, which is a periodic introduction of explosive oilinto the continuous stream of propellant water. Consequently, theabovementioned disadvantages inherent in valve-containing systems had tobe tolerated.

SUMMARY OF THE INVENTION An object of the present invention is to avoidthe prior art disadvantages inherent in the conventional processes andapparatus for conveying explosive oil.

Another object of the present invention is to provide an improvedprocess and apparatus for the conveyance of an explosive oil from onelocation to another which avoids the introduction of air into theconduit conveying system.

A further object of the present invention is to provide an im'- provedprocess and apparatus for the continuous conveyance v of an explosiveoil from one location to the other wherein the use of valves inoperating the conduits carrying the explosive therewith.

Other objects and further scope of applicability of the presentinvention will become apparent from the detailed description givenhereinafter; it should be understood, however, that the detaileddescription and specific examples, while indicating preferredembodiments of the invention, are given by way of illustration only,since various changes and modifications within the spirit and scope ofthe invention will become apparent to those skilled in the art from thisdetailed description.

Pursuant to the present invention, it has been found that theabove-mentioned disadvantages may be eliminated and a much improvedprocess and apparatus for the conveyance of an explosive oil from onelocation to another can be obtained by covering the explosive oil to beconveyed with water, drawing water into the conveying system when it isinitially used as well as each subsequent time the injector is put touse, thereafter continuously drawing explosive oil or alternatelyexplosive oil and water and finally, before the injector is stopped,again drawing water into the conduit conveying system until they arecompletely filled with said water.

Since water is drawn into the system during the initiation of theprocess as well as before shutting off the system, that is, during thecritical phases of the operation of the system, the entire conveyingsystem is completely filled with water during these operational phasesand explosive oil is introduced only when the injector has substantiallyreached its full suction power. As a result there is no air introducedinto the conduit conveying system and thus all of the above-mentioneddisadvantages are effectively eliminated. Due to this particular mode ofoperation according to the present invention, it is possible to operatethe conduits carrying explosive oil without any valve so that theabove-mentioned dangers associated with valve operation are likewiseavoided. In this connection it is of little or no importance withrespect to the mode of operation of the present invention at whichlocation the injector is provided.

In a further embodiment of the process and apparatus of the presentinvention the propellant water employed for conveying the explosive oiland for covering the explosive oil can be reused. Thus, on the one handa favorable water economy is obtained for the operation of the plantwhile on the other hand there is obtained the additional advantage thatafter the emulsion has been separated into explosive oil and water, thewater which still contains traces of the explosive oil need not besubjected to a waste water purification step since it is re-introducedinto the process. Additionally, the residues of explosive oil present inthe water are not lost.

In connection with the apparatus used for conducting the explosive oilconveying process of the present invention, it is proposed to make thesuction port of the injector and the tank or tanks containing theexplosive oil adjustable in height relative to each other. This can beaccomplished, for example, by connecting to the injector a flexiblesuction line wherein the end which is introduced into the explosive oiltank can be lifted and lowered by means of a lifting device. However, inplace of this device it is also possible to make the suction port of theinjector stationary and make the explosive oil tank or tanks liftableand lowerable by means of a lifting and lowering mechanism so that thesuction port can be positioned in the explosive oil or in the water, asdesired. The adjustability provided as a result of these features of thepresent invention is not dependent upon time, and is very advantageoussince it affords the flexibility of adapting well to the respectiveconditions and thus is substantially free from restrictions.

In order to ensure maximum safety, even in case of operating problems,it is further suggested to provide the adjusting device with a controlelement which automatically controls the adjusting device upon eachpurposeful and also involuntary interruption of the conveyance ofexplosive oil in such a manner that the injector suction port adjusts tobe in the water zone ofthe tank. In order to make sure that the conduitsystem in this case is also completely freed from explosive oil, anauxiliary source of pressurized water is suitably connected between theinjector and the pressurized water source, to the hydraulic line. Inthis connection, the hydraulic source and the auxiliary hydraulic sourcecan advantageously be in communication with each other in such a mannerthat the auxiliary hydraulic source is automatically actuated when thehydraulic source, although set into operation, does not yet supply therequired pressure for the propellant water.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become morefully understood from the detailed description given hereinbelow and theaccompanying drawings which are given by way of illustration only andthus are not limitative of the present invention and wherein FIGURE Ishows the relationship between the shock sensitivity of explosive oiland the size of air bubbles present therein,and

FIGURE 2 shows the explosive oil conveyance system of the presentinvention.

FIGURE 3 shows a lifting device for raising and lowering a tank asdefined by the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawingsthe apparatus of the present invention according to FIGURE 2 comprisestwo explosive oil tanks 1 and 2 which are in communication with eachother at their lowest point by means of conduit 4, so that the explosiveoil supplied to tank 2 via line 3 adjusts itself to the same level inboth tanks. The feeding of explosive oil into the container 2 iscontrolled by devices such as, liquid level control means, 27, a dualblocking means, in such a manner that the level of explosive oil in bothtanks 1 and 2 is always maintained between a maximum and a minimumlevel. Water is provided above the explosive oil in tanks 1 and 2. Theinjector 5 with the following conveying conduit llis provided outside ofthe container 1 at the level of the water zone and is supplied withpropellant water from the collecting tanks 6 using pump 7. The suctionline 9 which is connected to the injector at one of its ends isintroduced into tank 1 at its other free end, said free end beingliftable and lowerable by means of a lifting and lowering device 10, thestroke being set so that the end of the suction line is always in thelower terminal position, below the minimum level and, in the upperterminal position above the maximum level of the explosive oil level.Furthermore, the elevating mechanism is of such a construction that themouth of the suction line, when the system is shut off or if a breakdownin operation occurs, automatically adjusts to be in the water zone ofthe tank 1. The automatic adjustment is controlled by control means 28.The elevating device, which is not shown in detail, can functionpneumatically, as well as hydraulically or mechanically. The materialfor the suction line 9 should be as soft a substance as possible, forexample a rubber material or a synthetic resinous material which isresistant to explosive oil.

Water is provided in the tanks 1 and 2 above the explosive oil. Forbalancing the water level in tanks 1 and 2 the tanks communicate witheach other near the upper rim thereof by means of conduit 19. For theoverflow of excess water, conduit 20 is connected to tank 1 at the samelevel as the conduit 19. Conduit 20 leads to separator 21 which in turnis in communication with the propellant water tank 6 via conduit 22. Thepropellant water tank 6 is connected by a conduit 23, provided with acontrol valve, to a source of propellant water which is not shown, andvia outlet conduit 24 to a waste water station which is likewise notshown.

In order to insure that even in the case of breakdown the injector 5,the emulsion conduit 11, and the suction line 9 are freed from anyresidual explosive oil, fresh water line 25 is provided along withcontrol valve 26. In this case the check valve 8 prevents the watercoming from the fresh water source from flowing in the direction of thepropellant water collecting tank 6. In place of a fresh waterconnection, it is of course also possible to employ a storage tank ofpressurized water or another source of pressurized water.

The explosive oil drawn in via the suction line 9 is emulsified with thepropellant water in the injector and conducted in emulsion form throughconduit ll into separator 12 which separates the emulsion into explosiveoil and water. While the explosive oil is conducted via line 13 tofurther use or processing, the separated water flows through line 14 andsupply container 15 into the waste water collector 16 from where thepump 17 recycles the waste water via conduit 18 into the tank 2. In casethe separator 12 is at such a level that the waste water can flow byfree gravity flow from container 15 into the explosive oil tank 2, thewaste water collecting tank 16 and the pump 17 can accordingly beeliminated. By recycling the separated water into the tank 2 it ispractically ensured that tank 1 connected therewith is also neverwithout water, and in fact, will always be filled to overflow since inthis manner the entire propellant water flows through the tank 1. Evenif no explosive oil is in the tank, the system can still be operatedcontinuously with pure water.

From the illustration of FIGURE 2 it can be readily seen that not asingle valve is provided in the conduits of the entire system whichcarries explosive oil. Thus, it is of no significance whether thetransportation of the explosive oil or the explosive oil emulsion iscontinuous or is conducted by the socalled inoculation method. It ismerely a question of immersing the end of the suction line into theexplosive oil, or the length of time the mouth of the suction lineremains in the explosive oil and in the water. Likewise, it is of noimport for the process of the present invention whether only a singlestorage tank for the explosive oil is employed or, as in the example,two or more tanks are connected in series. However, the use of two ormore containers has the disadvantage when compared to using only asingle tank that any emulsion introduced into tank 2 is first separatedbefore it enters tank 1 from which the explosive oil is then withdrawnby the injector in pure form.

The arrangement of the injector 5 is of no significance in thearrangement and construction of the present invention. However, it isadvantageous to provide the injector at the height of the water zone,for example approximately to cm above the maximum level of the explosiveoil, since in this case the injector, when the system is not inoperation, is always filled with water due to the communication betweenthe injector 5 and the suction line 9.

As can be clearly seen from FIGURE 2, the lifting stroke of the suctionline 9 can be kept relatively small by providing the tanks 1 and 2 witha large inside cross section. in this connection, it is likewiseadvantageous if the transition from water intake to the intake ofexplosive oil and vice versa is conducted very slowly and smoothly incorrespondence with the speed of the lifting motion of the suction line.

In FIGURE 3, a lifting device 10 is illustrated wherein the height oftank 1 can be adjusted relative to the suction nozzle of the pipe line9. The range of height adjustability is greater than the differencebetween the maximum and minimum levels of the explosive oil in the tank.All of the other components in FIGURE 3 bear the same reference numeralsas shown in FIGURE 2.

In describing the process and apparatus for conveying explosive oil, forexample nitroglycerin, according to the present invention, the suctionnozzle of the suction pipe line 9 is disposed in the water layer of tank1 while the plant is in a standstill state. When the plant is put intooperation, water is first conveyed in this position and thereafter thesuction pipe line 9 is lowered by means of the lifting and loweringdevice 10 to the extent that the suction nozzle is immersed in thenitroglycerin. The nitroglycerin can now be transported. In thisconnection, it is of no importance whether or not the conveyance of thenitroglycerin is conducted continuously or by the so-called injectionprocess. In the injection process the suction pipe line 9 is lifted fromtime to time by means of the lifting unit 10 so that the suction nozzleis again immersed in the water layer and water is taken in.Subsequently, the suction pipe line is again lowered. Before the plantis shut down, the suction nozzle is lifted into the water layer andwater is drawn in until all of the pipe lines are filled with water andare free of nitroglycerin or nitroglycerin emulsion. The invention beingthus described, it will be obvious that the same may be varied in manyways. Such variations are not to be regarded as a departure from thespirit and scope of the invention, and all such modifications as wouldbe apparent to one skilled in the art are intended to be included.

We claim:

1. A process for the conveyance of an explosive oil from a container toa point of consumption which comprises maintaining a level of water overthe explosive oil in the container, drawing water from the containerthrough a suction conduit and introducing it into an emulsifying meansand into the conveying system at the beginning of the process, movingsaid container and said suction conduit relative to each other toposition the suction conduit in the water or the explosive oil layer,thereafter continuously drawing explosive oil or alternately explosiveoil and water from the container through a. suction conduit andintroducing it into an emulsifying means,

emulsifying the oil or oil/water mixture with propellant water suppliedto the emulsifying means, conveying the emulsion to a point ofconsumption and, before the'process is stopped, again drawing water fromthe container through the suction conduit into the system until theconduits in said system are filled with said water.

2. The process of Claim 1 wherein the explosive oil is introduced intothe system only when the emulsifying means has substantially reached itsfull suction power.

3. The process of Claim 1 wherein the propellant water employed forcovering and conveying the explosive oil is recycled for re-use.

4. The process of Claim 1 wherein an auxiliary source of pressurizedwater is introduced into the system at a point upstream of theemulsifying means.

5. A process for the conveyance of an explosive oil from a container toa point of consumption which comprises maintaining a level of water overthe explosive oil in the container, supplying propellant water to anemulsifying means, drawing water from the container through a suctionconduit and introducing it into the emulsifying means, moving thecontainer and the suction conduit relative to each other to position thesuction conduit in the water or the explosive oil layer, continuouslydrawing explosive oil or alternately explosive oil and water from thecontainer through the suction line and introducing it into theemulsifying means where it is emulsified with the propellant water andconducted in emulsion form to the point of consumption, and before theprocess is stopped, drawing water into the system until the conduits insaid system are filled with water.

6. The process of Claim 5 wherein the propellant water supplied to theemulsifying means is a pressurized water source.

7. The process of Claim 6 wherein an auxiliary source of pressurizedwater is supplied to the system between the propellant pressurized watersource and the emulsifying means and is actuated when the pressurizedpropellant water source although initiated does not yet supply therequired pressure to the emulsifying means.

8. The process of Claim 5 wherein the explosive oil in the container isalways maintained between a maximum and minimum level and the free endof the suction line for supplying said explosive oil to the emulsifyingmeans is always maintained below the minimumoil level or in the waterlevel above the maximum oil level. v

9. The process of Claim 5 wherein after the emulsi n is conveyed to thepoint of consumption it is separated into explosive oil and water, andthe water is thereafter recycled to the container for reuse.

10. The method of Claim 9 wherein excess water supplied to the containeris conveyed to a collecting tank where it is utilized as propellantwater to be supplied to the emulsifyingmeans.

ll. An apparatus for conveying an explosive oil froma container to apoint of consumption which comprises container means containingexplosive oil and a level of water covering said oil, an emulsifyingmeans communicating with the explosive oil and water in the containermeans by conduit means, said conduit means having a terminal free endportion extending intosaid container, means for changing the height ofthe free end of the conduit means disposed in said container means,means for supplying propellant water to the emulsifying means andconduit means for conveying the emulsion from the emulsifying means tothe point of consumption.

12. The apparatus of Claim 11 wherein a lifting and lowering device isassociated with the free end of the conduit means disposed in thecontainer.

13. The apparatus of Claim 12 wherein the stroke of the lift ing andlowering device is such that the free end of the conduit is below theminimum oil level in its lower terminal position and in the water levelabove the maximum oil level in its upper terminal position.

14. The apparatus of Claim 13, wherein the lifting and lowering deviceis provided with a means to dispose the free end of the conduit in thewater level upon any interruption of the process.

15. The apparatus of Claim 12, wherein the lifting and loweringmechanism functions pneumatically.

16. The apparatus of Claim 12, wherein the lifting and loweringmechanism functions hydraulically.

17. The apparatus of Claim 12, wherein the lifting and loweringmechanism functions mechanically.

18. The apparatus of Claim 11 wherein means are provided for raising andlowering the container means thereby changing the height of the free endof the conduit means disposed in the container.

19. The apparatus of Claim 11 wherein at the point of consumption, meansare provided for separating the emulsion into explosive oil and waterand the water is recycled to the container means.

20. The apparatus of Claim 19 wherein means are provided for conveyingexcess water supplied to the container means to a collecting tank fromwhere it is conveyed to the emulsifying means as propellant water.

21. The apparatus of Claim 11 wherein means are provided to maintain thelevel of explosive oil in the container means between a maximum andminimum value.

22. The apparatus of Claim 11 wherein means are provided for introducingan auxiliary source of water into the propellant water downstream of theemulsifying means.

23. An apparatus for conveying an explosive oil from a container to apoint of consumption which comprises container means containing anexplosive oil zone and a water zone disposed thereabove, an injectormeans communicating with the container means by conduit means, saidconduit means having a terminal free end portion extending into saidcontainer, means for changing the height of the free end of the conduitmeans disposed in said container means between the oil zone and thewater zone, means for supplying pressurized propellant water to theinjector means via conduit means, means communicating with saidpropellant water conduit means downstream of said injector means forsupplying auxiliary fresh water to the system, and conduit means forconveying the emulsion leaving the injector means to the point ofconsumption.

24. The apparatus of Claim 23 wherein the container means comprises twotanks which communicate with each other at their upper and lowerportions in the water zone and oil zone respectively to maintain thesame water-oil levels in said tanks.

25. The apparatus of Claim 23 wherein the injector means is provided atthe same level as the water zone in the container.

26. The apparatus of Claim 23 wherein means are provided for separatingthe water from the explosive oil at the point of consumption andrecycling the water to the container means.

27. The apparatus of Claim 23 wherein means are provided for recyclingexcess water from the container means to a collecting tank and pumpmeans are provided for conveying this water from the collecting tank tothe injector means as pressurized propellant water.

